Stamp



April 25, 1939. W. HUMPHNER 2,156,018

` STAMP Filed July 50, 1937 Patented Apr. 25, 1939` UNITED STATES PATENTOFFICE STAMP Ferdinand W. Humphncr, Oak Park, ,111., assignor, by mesneassignments, to Mid-States Gummed Paper Company, a corporation oi'Delaware Application July 30, 1937, Serial No. 156,565 s claim. (ci.'asa-s) This invention relates to a stamp or the like, applying brushwhen it is desired to apply a and is particularly useful in connectionwith a stamp to a parcel. When a customer has made sales tax stamp. apurchase, the stamp may be wetted in any In order to insure thecollection of sales taxes, suitable way and applied to the carton.' bag,conit has been customary to require dealers to issue tainer, receipt, orany other paperlevidence of y 5 certificates. One dilculty has been thetendency the sale. Where the tax is imposed upon services. of customersto disregard the certicates, leaving the gummed stamp may be applied tothe receipt them on the counter, etc., with the result that given forpayment of the service charge. the certificates may be used again. Anobject After the adhesive has been wetted for appli,-

of the present invention is to provide a simple cation, the imprinttends to break up and after 10 and effective means for preventing reuseof sales application the stamp cannot be reused because tax indiciawhile at the same time providing when the adhesive layer is removed fromthe obsimple and inexpensive means for insuring the ject to which it isapplied, the bottom imprint collection of the taxes. A further object isto is no longer intact and readable. A stamp tax provide a sales taxstamp which may be used in statute could prohibit the use of tax stamps154 large volume and with very simple procedure Where the imprint on thebottom is not intact whereby the taxes may be collected accurately andequivalent to the imprint on the top of the and eiectively while at thesame time requiring paper.

very little effort on the part of dealers, customers, Should the stampbe drawn from the roll and etc. Other specific objects and advantageswill separated for application but for some reason not 20 appear as thespeciilcation proceeds. applied to the container or receipt, thewetting' The invention is illustrated in a preferred em- 0f the adhesivestill serves to break up the imprint bodiment by the accompanyingdrawing in and prevent its reuse. At the same time, the whichheavy bodyof adhesive on one side of the stamp Figure 1 is a greatly enlarged sideView in elecauses the paper to curl until the stamp forms a 25 vation ofa sales vtax stamp or the like showing sealed roll, thus automaticallycancelling the the various layers making up the tax stamp body; stampfor effective application.

Fig. 2, a broken plan view of the stamps formed By applying serialnumbers to the rolls of in perforated strips for use in 4a roll, thestamps stamps, it is extremely simple for both the dealer being seriallynumbered; and Fig. 3, a side view and the tax auditor to determine thenumber of 30 in elevation of a. modiiled form of sales tax stamp sales,taxes due, etc. Further, the issuance of in which a uorescent gelatineor glue is used. rolls of stamps bearing serial numbers prevents Asillustrated more clearly in Fig. 1, the stamp duplication,counterfeiting, etc. body consists of a paper base having on its upperIn order to prevent counterfeiting of the stamp.

side an imprint; as for example, a sales tax imvarious methods may beused. For example, the 35 print of the type shown in Fig. 2. 0n itslower paper, print, or adhesive layers may be provided side, the s' ampbody is provided with a layer of with an invisible ink which becomesvisible upon adhesive of 'a type suitable for receiving an imtheapplication of water or other liquid. Also. print thereon. Preferably,the imprint on the if desired, a chemical indicator may be formed 40bottom of the adhesive is identical with the imin the paper, print, oradhesive and reacted with 40 print onnthe top of the paper. The adhesivelayer some fixed reagent. For example, beta naphthol on the bottom ofthe stamp is preferably colored dissolved in alcohol may be used in theglue, so as to provide a suitable background to receive paper or inkcoatings. In order to dissolve the the imprint, thus making the imprint,and beta naphthol, it is preferably tlrst mixed with particularly theserial number, stand out clearly potassium hydroxide and then dissolvedin 45 thereon. In view of the fact that printing upon alcohol. In orderto test this xed indicator in adhesive-is well known in the art at thepresent l, the stamp, I use a small amount of a dye salt time, it isbelieved .unnecessary to describe the Ydissolved ln alcohol. Instead ofbeta naphthol, adhesive and its constituents or the printing ink,naphtol A. S. may be used. There are a large etc. number of indicatorsknown to the trade which 50 In the use of the stamps, it is preferableto may be employed.

have them arranged in a roll with perforations If desired, variousmechanical means may be separating the individual stamps. The roll may.employed with the dispensing apparatus-for mufor convenience,besupportedin agumming matilating or injuring the stamp when it is fedchine and be fed one at a time over the waterthrough the device.However, it is often easy to n modify the dispensing devices so as toavoid such /muti1ation, and often such modification in dispensingdevices occurs through the wear of use. In the us'e of my invention, noapparatus need be 5 employed and the destruction of the imprint upon theadhesive is effected inevitably when the ad.

a stamp to the package or receipt, thus imposingl very little burdenupon the dealer. At the same time, the number and extent of sales can bedetermined readily by the auditor or dealer without counting the stampsindividually.

The printing of the design of the stamp upon the bottom of the adhesiveof each stamp tends to prevent the roll of stamps from adhering when thesame are formed into rolls. The imprint thus not only serves to identifyand establish the validity of the stamp in the eyes of the customer andto destroy the eiectiveness of the stamp when it is applied to anarticle, but also enables the stamps to be readily used ln roll formwithout adherence and thus permitting serial numbers to be employedeliectively with the stamps to determine at a glance how many have beenused.

In the modiiication shown in Fig. 3, I provide the stamp, label or thelike with a layer of gelatine or glue which becomes iluorescent when thestamp or label is shielded against ordinary daylight and conned to theultra violet ray. By the use of such a` layer of gelatine or glue, theidentity or genuineness of the stamp or label can be immediatelydetected by exposing the stamp to the ultra violet ray.

I prefer to employ a gelatine or glue which gives the desiredfluorescence upon exposure to the ray while at the same time remainingnon-adhesive or non-tacky. In the illustration given, the glue orgelatine layer is applied over the top imprint. However, if desired, thefluorescent glue or gelatine may be allowed to remain tacky or adhesiveand used on the bottom of the stamp or it may be used to cover theentire surface of the stamp.

In order to make a glue or gelatine which loses its adhesive or tackycharacteristics, I break down the viscosity or gel of the glue orgelatine by means of heat in a hydrolysis process. For example, agelatine with a viscosity of 170 mil., a gel of 488 grams, is mixed withwater on the basis of 3% pounds of gelatine to each gallon `of water.After soaking andmelting the solution, which at this point is veryviscous and is quite hard to pour, the solution is placed in anautoclave and heated for 45 minutes at an in- 160 C. The gelatine inthis case becomes very liquid and has lost its gelling power and makesan ideal material for imprinting and identifying stamps or labels byvirtue of its-fluorescent propc5 erty 7 5 portions of 1 to 3 pounds ofpepsin to every 100 ladhesive layer, and at ternal pressure of 90 poundsper square inch at being adapted to destroy said It. will be understoodthat the gelatine or glue ly dissolved in the propounds of glue orgelatine, dependent upon the grade. This is allowed to soak for twohours and is melted at a temperature of around 120 F. When the solutionis complete, concentrated hydrochloric acid is added to lower the pHfrom 3.5 to 4. The digestion starts at this point and continues untilthe'glue or gelatine is suiliciently liquefied. At this point,v thetemperature is raised to 170 F. to kill the enzymes and the solution mayor may not be neutralized with an alkali. As already stated,the stamp orlabel which is equipped with such a glue or gelatine can be readilydetected as to its genuineness by subjecting the stamp or label to ultraviolet rays, under which test the glue or gelatine becomes fluorescent.y

While I have shown certain specic means for carrying out the invention,it will be obvious that many modifications may be made without departingfrom the spiritof my invention. The foregoing detailed description hasbeen given for clearness of understanding only, and no unnecessarylimitations should be understood therefrom, but the appended claimsshould be construed as broadly as permissible, in view of the prior art.

l. A tax stamp comprising a paper base, an imprintv thereon, awater-soluble adhesive on the bottom of said pape and a thin imprint onsaid adhesive, said imprint being destroyed by the wetting of saidadhesive.

2. A roll of tax stamps joined together and provided with weakened linesof separation between 'the stamps, said stamps being numbered seriallyand each consisting of a paper layer provided on its underside with awater-soluble least one of said layers being provided with al materialnormally invisible but becoming visible upon the application of water.

3. A tax stamp of thecharacter set forth comprising a paper base layercarrying an imprint layer thereon, a water-soluble adhesive layer'at thebottom of said paper, and an imprint layer onAthe bottom of saidadhesive, at least one of said layers being provided with an indicatormaterial normally invisible but becoming visible upon the application ofwater for softening said adhesive. A

4. A roll of stamps having design imprintsguponv their upper sides,adhesive layers on their undersides, and designs `printed upon saidadhesive layers, said last-mentioned designs tending to preventadherence between the adhesive layer of one stamp and the adjacentsurface of another stamp when said stamps are stacked one upon theother. f

5. A roll of stamps each having an upper and a lower side provided withadhesive layer and having also the outer faces of said adhesive layersprovided with like designs bearing serial numbers, Isaid adhesive layerbeing water soluble and water is applied to the adhesive on the lowerside of the stamp.

6. A= stamp cpmprisinga paper base, an imprint thereon, an adhesivelayer on` the opposite lower design when side of the paper, an imprinton said adhesive and a layer of non-tacky gelatine 'carried by thesaine, said gelatine having the characteristic of becoming fluorescentwhen .exposed to ultraviolet rays.

'7. A tax stamp of the character set forthl comprising a paper base, animprint thereon,

adhesive for securing the stamp to a surface, and a layer of gelatinecarried by said stamp, said gelatine having the characteristic ofbecoming uorescent when exposed to ultra-violet rays.

8. A sizamp of the character sd: forth comprising a paper base, animprint on one side thereof, an adhesive layer on the opposite side ofsaid paper, and a gelatine layer over said imprint, said 'gelatine layerhaving the characteristic of becoming uorescent when exposed to ultra.-violet rays.

' FERDINAND W. HUMPHNER.

